A reclusive 40-year-old radio host with some serious communication issues hits a nasty midlife crisis in On Air (Parlez-moi de vous), an assured and emotionally astute feature debut for writer-director Pierre Pinaud. Backed by a tour-de-force turn from star Karin Viard (Polisse, Potiche), this well-tempered French dramedy delivers a fair share of laughs and tears without too much schmaltz, and should find plenty of listeners following its January 11 local release. Overseas, it reps the kind of broadly appealing Gallic fare that arthouse distribs should be tuning to.

Single and self-assured in all things except her own life, Claire Martin (Viard) hosts a nightly radio talk show where she offers smart, soothing advice to female callers experiencing various personal and sexual calamities. While the show is a major success, Claire – who adapts the professional pseudonym Melina, and whose real identity remains unknown to the public – is incapable of maintaining a normal off-the-air existence, confining herself to a germ-free apartment where she studies listeners’ letters and spends a considerable amount of time locked in a closet.

The origins of Claire’s distraught and hermitic lifestyle slowly come into view when she obtains the whereabouts of an elderly woman, Joelle (Nadia Barentin), who lives with her son and his family in a working-class Paris suburb. Claire soon begins mysteriously stalking Joelle, and her emotional investment in the affair, plus other pertinent clues, make it awfully clear that the woman may in fact be her mother. Eventually, she manages to infiltrate the family, befriending Joelle’s sensitive and smart-alecky step-grandson, Lucas (Nicolas Duvauchelle), who works in construction but has a talent for taking artsy photographic portraits.

Once the set-up is achieved, Pinaud (whose 2009 film, Les Miettes, won the Cesar award for best short) takes things in a direction that’s both poignant, sensitive and surprisingly rather funny. Forced to confront the demons of her past through Joelle, as well as her own social and romantic shortcomings through Lucas, Claire finds herself exposed on all fronts, moving through a number of sticky situations that are as touching as they are hilarious: In one terrifically played and executed scene, she’s forced to eat lunch with Lucas while the two sit at separate tables, locked in a conversation that reveals her myriad phobias and vulnerabilities, as well as her capacity for empathy and understanding.

In essence, Claire is incapable of practicing what she preaches on the air (the “the” seems to be missing from the English-language title), and though the narrative attempts to reverse that order, its conclusion reveals that such tasks are truly easier said than done.

Offering up a terrific performance that’s at once subtle and slightly outlandish, Viard manages to transform Claire’s hypersensitive, antisocial personality into a source of laughter, yet never shies away from her character’s darker inner traumas. Gallic bad boy Duvauchelle (White Material) is once again cast as a sort of tough guy here, though he tunes down his performance enough to make Lucas both intense and likeable. As the straight-talking Joelle, Barentin (The Round Up) provides a few short but heart-rending moments late in the game.

Pinaud and cinematographer Guillaume Deffontaines (All That Glitters) smartly keep the camera glued to the actors (this works particularly well for the scenes of Claire hosting her show), confining the action to a handful of settings thoughtfully designed by Marie Cheminal (Happy Few). Music by Maidi Roth is a bit mawkish and sometimes oversteps its boundaries, toeing a sentimental line that the film more or less avoids crossing.